A standard known as ANSI/TIA/EIA-41, Cellular Radiocommumications Intersystem Operations (hereinafter "ANSI-41"), defines how various nodes in a wireless communications network, including a Home Location Register ("HLR"), a Visiting Location Register ("VLR"), a Mobile Switching Center ("MSC") and a Message Center ("MC"), communicate with one another. Specifically, ANSI-41 defines what messages can be sent back and forth between the nodes and the contents of those messages.
The Message Waiting Notification ("MWN") service provides the functionality of informing a Mobile Station ("MS") of messages waiting in a mailbox. This service can be provided in one of two ways, including Message Waiting Indication ("MWI") and Message Waiting Tone ("MWT"). The MWI capability provides a visual indication of any messages waiting. For example, a lamp on the MS is turned on when messages are waiting in the subscriber's mailbox and is turned off when the messages are retrieved or if no messages are waiting. Optionally, the actual number of messages waiting can be shown on the display of the MS handset. This is accomplished by sending the ANSI-41 parameters MessageWaitingNotificationType ("MWNTYPE") and MessageWaitingNotificationCount ("MWNCOUNT") in the profile messages from the HLR to the MSC/VLR. Profile messages include regnot return result, qualreq return result, and QUALDIR INVOKE. The MWT capability provides the functionality of informing the MS of messages waiting in a mailbox by means of a tone at the beginning of call originations and terminations.
A subscriber's MWT and MWI capabilities are stored as part of the subscribers's profile in the HLR.
Currently, ANSI-41 contains detailed standards for communicating Message Waiting Notification ("MWN") information, including message type (e.g., voice or text) and message count, from the HLR to the MSC/VLR, but not from separate node, for example, a Service Node ("SN"), a Message Center ("MC"), a Voice Mail System ("VMS"), or an MSC where the VMS is hosted off the MSC, to the HLR. As used herein, the term "separate node"or "node" refers to either a separate node or a separate entity residing on the same node, such as in a case where the HLR, MSC, and VMS are co-located at the same node.
A standard known as the Simplified Message Desk Interface ("SMDI") is the only standard that defines the communication of MWN information to the HLR. SMDI suffers certain limitations, in that does not use ANSI-41 protocols and that it only supports one message type (voice) and does not support a message count.
Another "solution" has been to modify an existing ANSI-41 networking message known as the SMSREQ ("Short Message Service Request") message, which is typically sent by an MC to an HLR to request the MS's current SMS ("Short Message Service") routing address in order to send an SMS message directly to the MSC currently serving the MS. Using this message to communicate Message Waiting Notification ("MWN") information is done solely for convenience, since the message already exists between the MC and HLR; however, it is intended for SMS only, not the MWN service. Additionally, it does not make sense for an SMS message to be sent between a VMS and an HLR when SMS is not supported on the VMS. Moreover, it is typical, according to ANSI-41 naming conventions, for messages used to request information to end in "REQ", while messages used to direct a node to perform a task end in "DIR". Accordingly, using the SMSREQ message, which is a "request" message and, as such, is intended to request information, to provide information violates such naming conventions.
Therefore, what is needed is a message that utilizes existing ANSI-41 parameters to communicate MWN information, including multiple message types and a message count, from a separate node to the HLR.